多孔道结构复合金属氧化物气敏效应研究

项目名称： 多孔道结构复合金属氧化物气敏效应研究

项目编号： No.10876017

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 凌云汉

作者单位： 清华大学

项目金额： 33万元

中文摘要： （1）采用蒸发诱导自组装工艺制备了TiO2-SnO2、In2O3-SnO2以及Pd掺杂SnO2复合介孔氧化物薄膜。结果表明：SnO2、In2O3以及Pd的复合提高元件的气敏特性，0.5%Pd-SnO2元件在最佳工作温度175℃#19979;，对1000ppm氢气灵敏度为22.6。 （2）通过电位、温度和溶液环境控制实现了尺度可控高比表面二氧化钛纳米管阵列薄膜的合成与构造，利用等离子体改性获得丰富微结构和吸附态的多孔道敏感阵列，比较了不同气氛热处理对纳米阵列光电性能的影响。 （3）通过合金阳极氧化的方法获得了贵金属（Pd、Au）和过渡金属（W、V）原位复合的二氧化钛纳米管阵列薄膜；通过电化学沉积构筑出纳米管填充和外延的异质结敏感结构，为多元气氛检测提供了物质基础。 （4）考察了多孔道复合氧化物阵列器件的气体敏感特性，表明Pd和Au的掺杂可以显著提高H2和NO2的响应特性，并对增强机理进行了探讨。探索了光促气敏的可行性，初步研究结果表明染料敏化氧化钛纳米管阵列室温下对氢气具有敏感增强作用。 （5）完成了项目的研究任务。发表了SCI收录论文10篇（7篇IF>1.0）；EI收录论文5篇，申请发明专利2项。

中文关键词： 介孔材料；二氧化钛；纳米管阵列；气敏；肖特基势垒结

英文摘要： Thanks to their distinct properties on quantum size effect, surface and interface effect and small size effect, nanomaterials have great application and development values in the fields of thermodynamics, optical, electrical, catalysis etc. Mesoporous metal oxides with large specific surface area were successfully prepared by evaporation induced self-assembly process, and the dopant effects with metal oxide and noble metal on the gas sensing properties were investigated. Highly ordered nanotube array films were successfully prepared by anodic oxidation on titanium alloy substrates; and heterojuntions with catalytic effect were also expitally fabricated via electrochemical deposition method. The influence of tubular structure, the introduction of catalyst and light - bias effect on the device performance, as well as the basic sensing were also investigated. Our research will provide a theoretical basis and technical support on the development of high efficient and low temperature response for a multi gas detective sensor. The following progress has been made on this granted project: (1) TiO2-SnO2、In2O3-SnO2 and Pd doped SnO2 composite mesoporous oxides with pore size about 5nm and 6nm in diameter of particle were synthesized by evaporation induced self-assembly process, respectively. The results indicate that the introduction of SnO2、In2O3 and Pd promotes the sensing performance of the sensor. A premium operating temperature lower than 175℃and a sensitivity of 22.6 was obtained in the 0.5% Pd-SnO2 sensor on exposure to 1000ppm hydrogen. (2) Titanium dioxide nanotube array films with high specific surface area were synthesized and constructed through the control of potential, temperature and electrolyte environments, and sensing arrays with abundant microstructure and adsorption state were obtained via plasma modification. photoelectromical properties of nanotube array films treated at different atmospheres was also inestigated and compared. (3) Composite titanium dioxide nanotube arrays doped with noble metals (Pd, Au), transitional metals (W, V) were successfully fabricated via electrochemical oxidation of doping alloy precursors; and a new kind of filling and expital heterojunctions were formed by pulsed electrochemical deposition process. These works construct a solid basis for the gas detection in diverse atmosphere. (4) The gas sensing properties on H2, CO and NO2 were tested It was found that the inclusions of Pd and Au significantly promote the sensor performance. And the preliminary investigation revealed that light can also drive the gas sensor to response in room temperature. (5) The project was well accomplished and 10 research articles (7 papers with IF >1.0) were or to be published in journals cited by SCI; 5 papers were indexed by EI and 2 patents were pended.

英文关键词： mesoporous material;titanium dioxide; nanotube arry; gas sensing; Schottky barrier diode.